The Department of Justice on Tuesday followed through on warnings that it would sue Florida over the state’s plan to remove noncitizens from its voter rolls.

The lawsuit, filed in Federal District Court in Tallahassee, intensified a legal battle between the Obama administration and Republican leaders in Florida, a crucial swing state.

Florida has asked county election officials to remove up to 2,600 voters who may be registered illegally. But the federal government’s suit says the state’s list is “outdated and inaccurate.”

The suit also says Florida cannot remove voters 90 days before an election (the state’s primary will be held on Aug. 14) and must have the Justice Department approve any changes to how voters register.

“The Department of Justice has an overriding interest in protecting the rights of eligible citizens to register and vote free from unlawful burdens, while at the same time ensuring that ineligible persons do not register and vote in federal elections in violation of the law,” said Thomas E. Perez, assistant attorney general for the Justice Department’s Civil Rights Division.

The suit names the state and its secretary of state, Ken Detzner, as defendants.

On Monday, Florida filed its own lawsuit, against the Department of Homeland Security. Since September, the state has been asking for access to a federal immigrant database, maintained by the agency, that could help the state more accurately identify illegal voters.

Gov. Rick Scott, a Republican, in a television interview on Tuesday, defended the state’s efforts to remove ineligible voters and demanded that the state have access to the database.

“I have an obligation to enforce the laws of our land,” he said on CNN. “You don’t get to vote in Florida if you’re a non-U.S. citizen.”

Using driver’s license data, the state compiled a list of 182,000 voters who it said might not be citizens. It winnowed that list to 2,600 and asked county supervisors to contact each person on it. Those who could not prove their citizenship within 90 days would be removed from the voter rolls.

But county officials halted the effort on May 31. A lawyer for the Florida State Association of Supervisors of Elections found that most people on the list who had been contacted so far were legal voters. Among those contacted were recently naturalized immigrants and at least one who was a decorated war veteran.

Florida says it is following due process. Voters suspected of being noncitizens are given 90 days to prove their citizenship. They receive a letter notifying them of the uncertainty of their citizenship and, if they do not reply, a public notice is posted in a newspaper.

But civil rights groups say the effort has unfairly burdened hundreds of legal voters. On Friday, the American Civil Liberties Union sued Florida on behalf of two naturalized citizens.

So far, Florida has identified 85 voters who were registered illegally, Mr. Scott said. Voting without being a citizen is a third-degree felony, a category of crime punishable by up to five years in prison and up to $5,000 in fines.

A version of this article appears in print on June 13, 2012, on page A17 of the New York edition with the headline: Florida’s Approach to Purging Voter Rolls of Noncitizens Prompts Federal Lawsuit. Order Reprints|Today's Paper|Subscribe